Two members of the Guardians of the Galaxy almost had a much smaller role in Avengers: Infinity War and Avengers: Endgame. During a watch party of Guardians of the Galaxy Vol. 2, director James Gunn revealed Gamora and Nebula were initially only going to cameo in the Avengers films."Originally, they were solely going to cameo in Avengers 3, but by the time I was writing the screenplay for Vol. 2 it became something more," Gunn explained on Twitter.
Gunn expanded on the relationship between Gamora and Nebula in Guardians of the Galaxy Vol. 2, where they parted on good terms. Given that both sisters had a lifetime of horror inflicted upon them by Thanos, it made sense Gunn ended up giving them a larger role.
Ultimately, Gamora served as one of the emotional cores for Avengers: Infinity War, which saw Thanos confront her over the location of the Soul Stone. Traveling to the planet Vormir, Thanos sacrificed Gamora in order to gain control of the Stone. Likewise, Nebula played a large role in Avengers: Endgame, where she ran into her past self during the time travel mission to retrieve the Infinity Stones. A past version of Gamora also came to the present timeline; her whereabouts are currently unknown.
Written and directed by James Gunn, Guardians of the Galaxy Vol. 3 currently has no release date. The film is expected to begin production in February 2021.